*Well, the 'mysteries' of the ages huh?...Always the mysteries. The concensus of readers seems to be that the articfact 'once metal balls' are/were BALL BEARINGS. Who can tell...the Archaeogists can't...yet!

I have trouble understanding the Pyramid thing. The AZTEC Captial was built on Water/lakes...believe it or not...with floating gardens. We don't even have a precise ERA for a lot of what transpired in that land. Below...CHECK the LINK for the Aztec 'set up', peruse it and see if you come up with any ideas which could account for 'METAL BALLS'.